The article proposes a model of entrepreneurs and salaried employees’ behavior which explains their preference of informal employment to the official one in the conditions of a poorly-developed institutional environment and the decline of economic growth rates. Statistical data analysis performed for verification of the theoretical conclusions has shown that the amount of informally employed entrepreneurs depends on the technologies used and on the absence of possibilities to increase their income. Salaried employees choose the informal employment due to the lack of open-term employment contracts and absence of possibilities to increase their income, taking into account the existing taxation rates.